I did this in college. Dates went really well in my estimation until the guy tried to kiss me. I’d complain to my friends, who tried to convince me that a guy trying to kiss you isn’t supposed to ruin an otherwise good date, but I wasn’t having it.

Yeah, turns out I was exclusively into girls that decade and didn’t know it yet. I date men now, but sexuality can change over time and none of them did it for me back in the day.

It could be avoidant attachment, or splitting, or both as others have said, but they also might not fit your attraction map, and once it becomes a real option because they return your affections, you have to either deal with or ditch the real person, but it becomes impossible to stay with your fantasy of them